Emergence of the natural history of Myhre syndrome: 47 patients evaluated in the Massachusetts General Hospital Myhre Syndrome Clinic (2016-2023).

Myhre syndrome is an increasingly diagnosed ultrarare condition caused by recurrent germline autosomal dominant de novo variants in SMAD4. Detailed multispecialty evaluations performed at the Massachusetts General Hospital (MGH) Myhre Syndrome Clinic (2016-2023) and by collaborating specialists have facilitated deep phenotyping, genotyping and natural history analysis. Of 47 patients (four previously reported), most (81%) patients returned to MGH at least once. For patients followed for at least 5 years, symptom progression was observed in all. 55% were female and 9% were older than 18 years at diagnosis. Pathogenic variants in SMAD4 involved protein residues p.Ile500Val (49%), p.Ile500Thr (11%), p.Ile500Leu (2%), and p.Arg496Cys (38%). Individuals with the SMAD4 variant p.Arg496Cys were less likely to have hearing loss, growth restriction, and aortic hypoplasia than the other variant groups. Those with the p.Ile500Thr variant had moderate/severe aortic hypoplasia in three patients (60%), however, the small number (n = 5) prevented statistical comparison with the other variants. Two deaths reported in this cohort involved complex cardiovascular disease and airway stenosis, respectively. We provide a foundation for ongoing natural history studies and emphasize the need for evidence-based guidelines in anticipation of disease-specific therapies.

Coronal Diffusion-Weighted Imaging Does Not Improve Detection of Posterior Fossa Infarcts Compared With Conventional Axial Diffusion-Weighted Imaging.

PURPOSE: Recent publications have suggested incorporating coronal diffusion-weighted imaging (DWI) sequences and axial DWI sequences to enhance the detection of posterior fossa infarcts (PFIs). This study evaluated the utility of coronal DWIs compared with axial DWIs for assessing PFIs in the emergency department (ED). METHODS: A retrospective, institutional review board-approved study was conducted at a level I stroke center, including 118 patients who presented to the ED between 2016 and 2023 with suspected PFI. Inclusion criteria involved patients who underwent emergent 1.5 T magnetic resonance imaging (MRI) and had axial and coronal DWI sequences. Two neuroradiologists independently evaluated the DWI sequences for PFI detection in 2 rounds, with a 4-week interval between rounds. The neuroradiologists assessed the quality of axial and coronal DWIs using a 5-point Likert scale. Descriptive statistics, interrater reliability, and marginal homogeneity tests were performed. RESULTS: Among the 118 MRI scans, 23 (19%) showed PFI on axial and coronal DWI sequences. All 23 cases were identified on axial DWI, whereas 8 cases of PFI (35%) were not detected on coronal DWI (P value = 0.013). No PFIs were observed on coronal DWI that was not identified on axial DWI. The quality scores for both raters were significantly higher for axial DWIs than coronal DWIs (P value <0.00001). CONCLUSION: Despite recent recommendations advocating for the inclusion of coronal DWI in PFI detection, this study's findings indicate no improvement in PFI detection or image quality using coronal DWI. Further research is necessary to validate these results and explore the potential benefits of incorporating coronal DWI in assessing posterior fossa strokes.

Lowering Platelet Threshold to 20,000/µL for Fluoroscopy-Guided Lumbar Puncture Does Not Result in Observed Clinical Adverse Outcomes.

PURPOSE: Fluoroscopic-guided lumbar puncture (FG-LP) is a common neuroradiologic procedure. Traditionally, a minimum platelet count (MPC) of 50,000/µL for this procedure has been required; however, we recently adopted a lower MPC threshold of 20,000/µL. The purpose of this study was to compare adverse events in patients undergoing FG-LP with MPCs above to those below the conventional 50,000/µL threshold. MATERIALS: This was an institutional review board-approved, retrospective study on adult patients with hematologic malignancy undergoing FG-LP in the neuroradiology division between May 2021 and December 2022, after lowering the minimal required MPC to 20,000/µL. Recorded data included indication for FG-LP, preprocedure and postprocedure MPC, need for and number of platelet transfusions within 24 hours of FG-LP, presence of traumatic tap, FG-LP-related complications, and any platelet transfusion-related adverse event. Patients were classified into 2 groups based on MPC: (1) those above 50,000/µL and (2) those below 50,000/µL. Descriptive statistics were used comparing these 2 groups. RESULTS: One hundred twenty-eight patients underwent FG-LP, with 46 having an MPC between 20,000 and 50,000/µL and 82 having an MPC above 50,000/µL. No postprocedural complications were encountered in either group. Traumatic taps occurred in 10/46 (22%)​ with MPC below 50,000/µL versus 10/82 (12%)​ in those with MPC above 50,000/µL. Forty of 46 patients (87%) were transfused with platelets within 24 hours prior to FG-LP. One patient developed a transfusion-related reaction. CONCLUSION: Lowering the MPC threshold from 50,000/µL to 20,000/µL for FG-LP did not result in a higher incidence of spinal hematoma.

Correlating Evans Index, Callosal Angle, and Lateral Ventricle Volume With Gait Response Outcomes in Idiopathic Normal Pressure Hydrocephalus Diagnosis.

OBJECTIVE: Radiological imaging is pivotal in diagnosing idiopathic normal pressure hydrocephalus (iNPH), given the similarity of its symptoms to other neurodegenerative diseases. We aimed to correlate the Evans index (EI), callosal angle (CA), and the volume of the lateral ventricles measured before cerebrospinal fluid removal with the resultant outcomes in gait response. METHODS: In our retrospective study, we identified 42 patients with a diagnosis of iNPH. These patients underwent gait analysis, imaging, and lumbar puncture. Radiological assessments included measurements of CA EI and lateral ventricular volume. Clinically, we assessed the following 4 gait parameters: cadence, gait speed, stride length, and timed up and go. Change in the 4 gait parameters was calculated, normalized, and compiled into a composite score, following which the group was divided into 'responders' and 'nonresponders' based on z score of 0.5. Our dependent variable was clinical improvement in gait, and our independent variables included lateral ventricular volume, EI, and CA. We performed a Wilcoxon rank-sum test to compare significant responder status using CA, EI, and lateral ventricle volume. A receiver operating characteristic analysis was employed to determine which volume measurement exhibited the strongest correlation with responder status. Determining the significant variables, a chi-square analysis was subsequently conducted.A significance threshold was set at P < 0.05. All our statistical evaluations were conducted in the Spyder environment, which is compatible with Python 3.10. RESULTS: There was a significant difference for responder status in EI and lateral ventricle volume. Evan index showing a statistic of 2.202 (P value = 0.02) and lateral ventricle volume demonstrating a statistic of 2.086 (P value = 0.03). Subsequent exploration using receiver operating characteristic analysis, with area under the curve of 0.71, identified 105.40 cm3 as the most robustly correlated volume threshold with responder status. CONCLUSIONS: The lateral ventricular volume demonstrates a stronger correlation with gait improvement compared to the CA or EI. These observations indicate that evaluating the lateral ventricle volume before lumbar puncture could serve as a predictor for gait response after lumbar puncture in individuals with normal pressure hydrocephalus.

Fully automated 3D machine learning model for HPV status characterization in oropharyngeal squamous cell carcinomas based on CT images.

BACKGROUND: Human papillomavirus (HPV) status plays a major role in predicting oropharyngeal squamous cell carcinoma (OPSCC) survival. This study assesses the accuracy of a fully automated 3D convolutional neural network (CNN) in predicting HPV status using CT images. METHODS: Pretreatment CT images from OPSCC patients were used to train a 3D DenseNet-121 model to predict HPV-p16 status. Performance was evaluated by the ROC Curve (AUC), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and F1 score. RESULTS: The network achieved a mean AUC of 0.80 ± 0.06. The best-preforming fold had a sensitivity of 0.86 and specificity of 0.92 at the Youden's index. The PPV, NPV, and F1 scores are 0.97, 0.71, and 0.82, respectively. CONCLUSIONS: A fully automated CNN can characterize the HPV status of OPSCC patients with high sensitivity and specificity. Further refinement of this algorithm has the potential to provide a non-invasive tool to guide clinical management.

Multisystem factors contributing to redundant intracranial vascular imaging in the ED.

PURPOSE: To evaluate the multisystem factors contributing to redundant neurovascular orders in the ED. METHODS: This was an IRB-approved, retrospective study, performed at a single institution examining a 5-year history of redundant CTA/MRA head and neck (HN) exams performed in the ED for patients with no documented clinical change in mental status/neurological exam necessitating additional imaging. Factors contributing to redundant ordering including provider experience, synchronous order placement, and radiologist recommendations were examined. Additionally, the impact of duplicative imaging in terms of medical cost and ED length of stay was evaluated. RESULTS: 250 patients met inclusion criteria with both CTA/MRA of the HN performed during a single ED encounter (total 500 exams). 190 (76%) redundant exams were not recommended by a radiologist and contributed to an added ED length of stay of 3.6 h on average. Provider experience was not a significant contributing factor. 60 (24%) of redundant exams were recommended by a radiologist and were most frequently CTAs needed to clarify an area of artifact/high-grade stenosis/occlusion on a primary MRA exam. CONCLUSION: Evaluation of contributing factors to redundant CTA/MRA HN exams ordering has highlighted multiple associated factors including provider experience, recommendations by radiologists for clarification of MRA findings, as well as systems processes related to synchronous CTA/MRA order placement.

Volumetric Changes in the Choroid Plexus Associated with Spontaneous Intracranial Hypotension in Patients with Spinal CSF Leak.

BACKGROUND AND PURPOSE: The choroid plexus contains specialized ependymal cells responsible for CSF production. Recent studies have demonstrated volumetric and perfusion changes in the choroid plexus with age and neurodegenerative disorders, however, volumetric changes in the choroid plexus in low pressure states is not known. The purpose of this study is to evaluate volumetric differences in choroid plexus size in patients with spontaneous intracranial hypotension (SIH) resultant from spinal CSF leaks compared with healthy controls. MATERIALS AND METHODS: This was a retrospective, institutional review board-approved study. Patients with MRI evidence of SIH and a spinal CSF leak diagnosed on myelography and subsequently confirmed at surgery were included in this study. All patients included in this study including age-matched healthy controls had a brain MRI performed on a either a 1.5 or 3T scanner with acquisition of 3D T1 postcontrast (eg, BRAVO, MPRAGE, etc). In all patients, the trigonum ventriculi volume, in the atria of the lateral ventricles, was contoured by using Visage-7 segmentation tools on the volumetric postcontrast T1 sequence. A basic 2-tailed t test was used to compare choroid plexus volumes between the 2 groups. RESULTS: Thirty-four patients were included with 17 patients with SIH with spinal CSF leak and 17 healthy control patients who were age- and sex-matched. The mean age of patients was 45 years, standard deviation 14 years. The mean volume of the choroid plexus for patients with SIH with spinal CSF leak was 1.2 cm3 (standard deviation = 0.26) compared with 0.63 cm3 (standard deviation = 0.31) in the control group (P < .0001). CONCLUSIONS: Results of this study demonstrate a higher choroid plexus volume in patients with SIH with spinal CSF leak compared with age- and sex-matched healthy controls. This likely reflects compensatory mechanisms to counteract intracranial hypotension by increasing CSF production as well as increased vascularity of the choroid plexus through expansion of the intracranial blood pool.

Non-contrast MRI Surveillance of Craniopharyngiomas using a balanced steady state free precession (bSSFP) sequence.

BACKGROUND AND PURPOSE: Contrast-enhanced MRI (CEMRI) is a commonly used imaging modality for craniopharyngioma surveillance; however, it carries risks such as allergic reaction and gadolinium deposition. This study evaluates the efficacy of non-contrast enhanced MRI (NCMRI) with a balanced steady state free precession (bSSFP) sequence compared with CEMRI T1-weighted imaging for craniopharyngioma surveillance. MATERIALS AND METHODS: 29 craniopharyngioma patients (16 female/13 male, mean age=21.5± 4.3 years) with CEMRIs including a bSSFP sequence were evaluated. For each patient, 2 blinded neuroradiologists compared the dimensions of residual craniopharyngioma on noncontrast and contrast-enhanced sequences. Tumor volume and solid/cystic component measurements were evaluated using paired t-tests. Diagnostic confidence levels for NC-and CE evaluations were measured using a 3-point scale (2=confident,1=adequate,0=unsure). Analyses of tumor involvement of cranial nerves and adjacent vasculature and diagnostic confidence were performed using Fisher's exact and chi-square tests. RESULTS: No significant difference was observed between residual tumor volumes in both studies (18.86±21.67 cm3 vs 17.64±23.85 cm3, p=0.55) and measurements of dominant solid component volume, number of cystic components, and largest cystic component volume (2.71±3.47 cm3 vs 3.95±5.51 cm3, p=0.10; 2.5±1.5 vs 2.9±1.5, p=0.10; 7.61±13.41 vs 6.84±13.37 cm3, p=0.22, respectively). Tumoral involvement of cranial nerves II (p=0.64), III (p=0.42), and adjacent vasculature (p=0.05) showed no significant differences in detection. Diagnostic confidence was comparable evaluating cranial nerve II, vascular structures, and third ventricle (p>0.05) involvement. Higher levels of confidence were observed with bSSFP sequences for detection of cranial nerve III involvement (p=0.0001) and with ce-T1W for cavernous sinus involvement (p=0.02). CONCLUSIONS: NCMRI techniques using a bSSFP sequence provides similar characterization of craniopharyngiomas as contrast enhanced techniques. ABBREVIATIONS: 3D DRIVE, 3-dimensional driven equilibrium; ACA, anterior cerebral artery; bSSFP, balanced steady-state free precession; ce-T1W, contrast-enhanced T1-weighted imaging; CN, cranial nerve; GTR, gross total resection; STR, subtotal resection.

Predicting Gait Speed Improvement in Idiopathic Normal Pressure Hydrocephalus Patients: The Role of Evans Index and Ventricular Volume.

Objective This study aims to investigate the association between specific imaging parameters, namely, the Evans index (EI) and ventricular volume (VV), and the variation in gait speed observed in patients with idiopathic normal pressure hydrocephalus (iNPH) before and after cerebrospinal fluid (CSF) removal/lumbar drain (LD). Furthermore, it seeks to identify which imaging parameters are the most reliable predictors for significant improvements in gait speed post procedure. Methods In this retrospective analysis, the study measured the gait speed of 35 patients diagnosed with idiopathic normal pressure hydrocephalus (iNPH) before and after they underwent CSF removal. Before lumbar drain (LD), brain images were segmented to calculate the Evans index and ventricular volume. The study explored the relationship between these imaging parameters (the Evans index and ventricular volume) and the improvement in gait speed following CSF removal. Patients were divided into two categories based on the degree of improvement in gait speed, and we compared the imaging parameters between these groups. Receiver operating characteristic (ROC) curve analysis was employed to determine the optimal imaging parameter thresholds predictive of gait speed enhancement. Finally, the study assessed the predictive accuracy of these thresholds for identifying patients likely to experience improved gait speed post-LD. Results Following CSF removal/lumbar drain, the participants significantly improved in gait speed, as indicated by a paired sample t-test (p-value = 0.0017). A moderate positive correlation was observed between the imaging parameters (EI and VV) and the improvement in gait speed post-LD. Significant differences were detected between the two patient groups regarding EI, VV, and a composite score (statistical test value = 3.1, 2.8, and 2.9, respectively; p-value < 0.01). Receiver operating characteristic (ROC) curve analysis identified the optimal thresholds for the EI and VV to be 0.39 and 110.78 cm³, respectively. The classification based on these thresholds yielded significant associations between patients displaying favorable imaging parameters and those demonstrating improved gait speed post-LD, with chi-square (χ²) values of 8.5 and 7.1, respectively, and p-values < 0.01. Furthermore, these imaging parameter thresholds had a 74% accuracy rate in predicting patients who would improve post-LD. Conclusion The study demonstrates that ventricle volume and the Evans index can significantly predict gait speed improvement after lumbar drain (LD) in patients with iNPH.

Trends in non-focal neurological chief complaints and CT angiography utilization among adults in the emergency department.

Prudent imaging use is essential for cost reduction and efficient patient triage. Recent efforts have focused on head and neck CTA in patients with emergent concerns for non-focal neurological complaints, but have failed to demonstrate whether increases in utilization have resulted in better care. The objective of this study was to examine trends in head and neck CTA ordering and determine whether a correlation exists between imaging utilization and positivity rates. This is a single-center retrospective observational study at a quaternary referral center. This study includes patients presenting with headache and/or dizziness to the emergency department between January 2017 and December 2021. Patients who received a head and neck CTA were compared to those who did not. The main outcomes included annual head and neck CTA utilization and positivity rates, defined as the percent of scans with attributable acute pathologies. Among 24,892 emergency department visits, 2264 (9.1%) underwent head and neck CTA imaging. The percentage of patients who received a scan over the study period increased from 7.89% (422/5351) in 2017 to 13.24% (662/5001) in 2021, representing a 67.4% increase from baseline (OR, 1.14; 95% CI 1.11-1.18; P < .001). The positivity rate, or the percentage of scans ordered that revealed attributable acute pathology, dropped from 16.8% (71/422) in 2017 to 10.4% (69/662) in 2021 (OR, 0.86; 95% CI 0.79-0.94; P = .001), a 38% reduction in positive examinations. Throughout the study period, there was a 67.4% increase in head and neck CTA ordering with a concomitant 38.1% decrease in positivity rate.

Evaluation of an Artificial Intelligence Model for Identification of Mass Effect and Vasogenic Edema on CT of the Head.

BACKGROUND AND PURPOSE: Mass effect and vasogenic edema are critical findings on CT of the head. This study compared the accuracy of an artificial intelligence model (Annalise Enterprise CTB) with consensus neuroradiologists' interpretations in detecting mass effect and vasogenic edema. MATERIALS AND METHODS: A retrospective stand-alone performance assessment was conducted on data sets of noncontrast CT head cases acquired between 2016 and 2022 for each finding. The cases were obtained from patients 18 years of age or older from 5 hospitals in the United States. The positive cases were selected consecutively on the basis of the original clinical reports using natural language processing and manual confirmation. The negative cases were selected by taking the next negative case acquired from the same CT scanner after positive cases. Each case was interpreted independently by up-to-three neuroradiologists to establish consensus interpretations. Each case was then interpreted by the artificial intelligence model for the presence of the relevant finding. The neuroradiologists were provided with the entire CT study. The artificial intelligence model separately received thin (≤1.5 mm) and/or thick (>1.5 and ≤5 mm) axial series. RESULTS: The 2 cohorts included 818 cases for mass effect and 310 cases for vasogenic edema. The artificial intelligence model identified mass effect with a sensitivity of 96.6% (95% CI, 94.9%-98.2%) and a specificity of 89.8% (95% CI, 84.7%-94.2%) for the thin series, and 95.3% (95% CI, 93.5%-96.8%) and 93.1% (95% CI, 89.1%-96.6%) for the thick series. It identified vasogenic edema with a sensitivity of 90.2% (95% CI, 82.0%-96.7%) and a specificity of 93.5% (95% CI, 88.9%-97.2%) for the thin series, and 90.0% (95% CI, 84.0%-96.0%) and 95.5% (95% CI, 92.5%-98.0%) for the thick series. The corresponding areas under the curve were at least 0.980. CONCLUSIONS: The assessed artificial intelligence model accurately identified mass effect and vasogenic edema in this CT data set. It could assist the clinical workflow by prioritizing interpretation of cases with abnormal findings, possibly benefiting patients through earlier identification and subsequent treatment.

Implementation of a Survey Spine MR Imaging Protocol for Cord Compression in the Emergency Department: Experience at a Level 1 Trauma Center.

BACKGROUND AND PURPOSE: Imaging stewardship in the emergency department (ED) is vital in ensuring patients receive optimized care. While suspected cord compression (CC) is a frequent indication for total spine MR imaging in the ED, the incidence of CC is low. Recently, our level 1 trauma center introduced a survey spine MR imaging protocol to evaluate for suspected CC while reducing examination time to avoid imaging overutilization. This study aims to evaluate the time savings, frequency of ordering patterns of the survey, and the symptoms and outcomes of patients undergoing the survey. MATERIALS AND METHODS: This retrospective study examined patients who received a survey spine MR imaging in the ED at our institution between 2018 and 2022. All examinations were performed on a 1.5T GE Healthcare scanner by using our institutional CC survey protocol, which includes sagittal T2WI and STIR sequences through the cervical, thoracic, and lumbar spine. Examinations were read by a blinded, board-certified neuroradiologist. RESULTS: A total of 2002 patients received a survey spine MR imaging protocol during the study period. Of these patients, 845 (42.2%, mean age 57 ± 19 years, 45% women) received survey spine MR imaging examinations for the suspicion of CC, and 120 patients (14.2% positivity rate) had radiographic CC. The survey spine MR imaging averaged 5 minutes and 50 seconds (79% faster than routine MR imaging). On multivariate analysis, trauma, back pain, lower extremity weakness, urinary or bowel incontinence, numbness, ataxia, and hyperreflexia were each independently associated with CC. Of the 120 patients with CC, 71 underwent emergent surgery, 20 underwent nonemergent surgery, and 29 were managed medically. CONCLUSIONS: The survey spine protocol was positive for CC in 14% of patients in our cohort and acquired at a 79% faster rate compared with routine total spine. Understanding the positivity rate of CC, the clinical symptoms that are most associated with CC, and the subsequent care management for patients presenting with suspected cord compression who received the survey spine MR imaging may better inform the broad adoption and subsequent utilization of survey imaging protocols in emergency settings to increase throughput, improve allocation of resources, and provide efficient care for patients with suspected CC.